engleski

DNA Methylation During Somatic Embryogenesis of Picea omorika

The DNA methylation of Picea omorika line BB19, in correlation with embryogenic potential and embryo maturation, was investigated. Cytosine methylation level was detected using random amplification coupled with restriction enzyme digestion. The long– term embryogenic cultures were maintained on the induction medium (IM): basic LP supplemented with 2, 4-D and BA. A four-week pretreatment on a medium with reduced hormone content (1/2 hormones or BA alone), or one-week pretreatment on hormone-free medium with activated charcoal was applied in order to increase maturation capability of embryogenic lines. IM supplemented with hypomethylation drug 5-azaC was used as a control. Maturation medium (MM) was &frac12 ; ; LP supplemented with ABA. The significantly low DNA methylation correlated with high embryogenic potential and high frequency of mature embryos in tissue precultured on medium with activated charcoal. The good maturation potential coincided with low DNA methylation of the tissue precultured on IM supplemented only with BA. Contrary, addition of 5-azaC blocked embryo maturation, although it stimulated decrease of DNA methylation level. The half-strength concentrations of 2, 4-D and BA stimulated embryo maturation and reduced DNA methylation. However, the loss of embryogenic potential was significant in comparison with other tested media.

DNA methylation; embryo development; somatic embryogenesis; Picea omorika (Panč.) Purk

nije evidentirano